A storage area network (SAN), which may also be called a Fabric network, includes terminal systems (referred to as nodes, including servers and storage devices), and intermediate systems (referred to as switches). According to Fibre Channel (FC) protocols, a Fabric network can support a limited number, e.g. up to 239, FCoE Forwarder (FCF) switches. This restricts the size of the network. In order to overcome the restriction of 239 FCF switches, devices called N-Port Virtualizer (NPV) may be added between nodes and FCF switches. These NPVs serve as agents for the nodes to register to the Fabric network. An NPV has its F ports connected to N_Ports (i.e., Node ports) of nodes, and is treated as an FCF switch by the nodes. An NPV also has its NP ports connected to F_Ports (i.e., Fabric ports) of FCF switches, and is treated as a node by the FCF switches (also referred to as FCF). Plural NPVs may be connected in series in the network. As long as one of the NPVs is connected to an FCF switch, all of the plural NPVs and nodes served by the NPVs can register in the Fabric network via the NPV.